Paving blocks in recent years have had a resurgence in their desirability for forming of surfaces for not only utilitarian surfaces, but also for decorative purposes as to residential driveways and other areas such as patios or similar function areas. Paving bricks which had heretofore fulfilled this need have generally become unavailable and the clay-based bricks now available do not have the structural characteristics that are suitable for many of these purposes and in particular are not suitable for driveways or other areas which are subjected to relatively high compressive forces. In an effort to meet this need for paving blocks having the requisite compressive structural strength, techniques have been developed to fabricate paving blocks from cement and sand mixtures. The basic technique that has developed is a technique whereby the cement, sand and water mixture is subjected to a substantial compressive force during the process of molding the desired article so as to develop the desired compessive strength. These paving blocks are alternatively known in the trade as paving stones and are also frequently referred to as paving bricks. Use of the term "paving block" in this specification and claims is not intended to be a limitation on the scope, but is to be construed as inclusive of the other terms or any terms that are of similar import.
Concurrently with development of the compression molding techniques to achieve the desired compressive strength and hardness of the resultant paving product there have been attempts to develop design configurations that would enhance the ability of the paving block to cooperatively interlock in a manner to resist lateral displacing forces. This aspect is particularly important as to paving blocks utilized in forming of paving surfaces such as for residential driveways or even for industrial driveways that are subjected to utilization by vehicles of relatively great weight that would otherwise tend to cause the blocks to be first displaced in a vertical direction and as a resultant consequence to then be laterally displaced. Various configurations of paving blocks have been developed as to their peripheral shape to effect the desired stability and resistance to lateral displacement through achieving mechanical interlocking of the adjacently disposed blocks. However, development of complexity of peripheral configurations of the paving block to resist lateral displacement has invariably resulted in a similar increase in the difficulty of placing or laying of the blocks on the surface to be covered. An increase in the complexity of laying the blocks thus results in increase in the cost of installation and thus economically detracts from the attractiveness of the paving blocks even though the blocks may be mechanically efficient to resist displacement forces and to also provide an aesthetic appearance.